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UNIVERSITY  OF  ILLINOIS, 

Agricultural  Experiment  Station 


URBANA,   APRIL,    1897. 


BULLETIN  No.  48. 


THE  SAN  JOSE  SCALE  IN  ILLINOIS* 

IMPORTANCE  OF  THE  SAN  JOSE  SCALE. 

"There  is  perhaps  no  insect  capable  of  causing  greater  dam- 
age to  fruit  interests  in  the  United  States,  or  perhaps  the  world, 
than  the  San  Jose,  or  pernicious,  scale.  It  is  not  striking  in 
appearance,  and  might  often  remain  unrecognized,  or  at  least 
misunderstood,  and  yet  so  steadily  and  relentlessly  does  it  spread 
over  practically  all  deciduous  fruit-trees — trunk,  limbs,  foliage, 
and  fruit — that  it  is  only  a  question  of  two  or  three  years  before 
the  death  of  the  plant  attacked  is  brought  about,  and  the  possi- 
bility of  injury,  which,  from  experience  with  other  scale  enemies 
of  deciduous  plants,  might  be  easily  ignored  or  thought  insignifi- 
cant, is  soon  startlingly  demonstrated.  Its  importance  from  an 
economic  standpoint  is  vastly  increased  by  the  ease  with  which 
it  is  distributed  over  wide  districts  through  the  agency  of  nursery 
stock  and  the  marketing  of  fruit,  and  the  extreme  difficulty  of 
exterminating  it  where  once  introduced,  presenting,  as  it  does  in 
the  last  regard,  difficulties  not  found  with  any  other  scale  insect. 
Its  importance  was  early  recognized  by  Professor  Comstock,  who 
in  first  describing  it  in  1880  gave  it  the  suggestive  name  of  perni- 
ciosus,  saying  of  it  that  it  is  the  most  pernicious  scale  insect  known 
in  this  country.  The  Los  Angeles  Horticultural  Commission 
reported  in  1890  that  if  this  pest  be  not  speedily  destroyed  it  will 
utterly  ruin  the  deciduous  fruit  interests  of  the  Pacific  Coast.  Its 

*This  article  is  based  upon  a  paper  read  by  the  writer  to  the  State  Horticultural 
Society  at  its  meeting  in  Springfield,  111.,  Dec.  30,  1896.  413  . 


414  BULLETIN  NO.  48.  \_April, 

capacity  for  evil  has  been  more  than  demonstrated  since  its  appear- 
ance in  the  East,  and  it  has  been,  if  anything,  more  disastrous  to 
the  peach  and  pear  orchards  of  Maryland,  New  Jersey,  and  other 
Eastern  and  Southern  States  than  in  California  and  the  West. 

"We  are  therefore  justified  in  the  assertion  that  no  more 
serious  menace  to  the  deciduous  fruit  interests  of  this  country  has 
ever  been  known.  There  is  no  intention  here  to  arouse  unneces- 
sary alarm,  but  merely  to  emphasize  the  importance  of  taking  the 
utmost  precautions  to  prevent  its  introduction  into  new  localities, 
and  to  point  out  the  extreme  necessity  of  earnest  effort  to  stamp 
it  out  where  it  has  already  gained  a  foothold." 

The  foregoing  sentences  are  from  a  bulletin  on  the  San  Jose 
scale  published  in  1896  by  the  United  States  Department  of 
Agriculture.*  Its  authors,  Messrs.  Howard  and  Marlatt,  have 
been  for  a  long  time  in  the  Division  of  Entomology,  at  Washing- 
ton, Mr.  Howard  being  now  its  Chief;  and  they  have  thus  for 
many  years  been  made  continuously  acquainted  with  the  history 
and  spread  of  this  scale,  have  personally  studied  it  at  many 
different  localities,  and  have  obtained  information  concerning  it 
from  all  parts  of  the  United  States  infested  by  it.  No  one  else 
can  speak  with  such  authority  on  the  subject  of  its  injuries  to  hor- 
ticulture, and  few  are  less  likely  to  make  extreme  or  sensational 
statements  concerning  it. 

My  own  brief  experience  with  it  fully  bears  out,  as  far  as  it 
goes,  the  statements  above  quoted.  For  example,  a  single  orchard- 
ist  in  this  State  has  already  lost  a  thousand  trees,  killed  by  this 
scale,  notwithstanding  very  considerable  efforts  on  his  part  to  dis- 
lodge it,  and  his  present  orchard  property  of  some  seven  hundred 
trees  is  all  thoroughly  infested.  From  this  place,  near  Sparta,  in 
Randolph  county,  the  pest  has  overflowed  into  surrounding 
orchards,  and  has  possibly  been  distributed  elsewhere,  no  one 
knows  how  far  nor  in  what  amount.  Furthermore,  observations 
made  within  the  last  year  in  Delaware!  seem  to  show  that  this 
scale  is  much  more  difficult  to  eradicate  and  that  it  tends  to  spread 
more  rapidly  than  has  heretofore  been  supposed.  The  Experi- 
ment Station  Entomologist  of  that  State  reports  that  where  he 
found  but  fifty  infested  trees  last  year  he  now  finds  a  thousand, 
although  energetic  insecticide  measures  have  been  taken  in  the 
meantime  ;  and  he  further  concludes  that  the  entire  orchard  must 
be  thoroughly  treated  in  every  case  where  even  so  much  as  a 
single  tree  is  found  visibly  infested. 

"  The  San  Jos6  Scale;  its  Occurrences  in  the  United  States,  with  a  full  Account  of 
its  Life  History  and  the  Remedies  to  be  used  against  it." 
fBull.  XXXIII.,  Del.  Agr.  Exper.  Station. 


1897.]  SAN   JOSE   SCALE   IN   ILLINOIS.  415 

When  to  this  general  report  of  injuries  done  by  this  scale 
insect  elsewhere  I  add  the  ominous  statement  that  we  have  found 
within  the  last  seven  months  fifteen  widely  separated  localities  in 
Illinois  upon  which  the  San  Jose  scale  has  securely  fastened 
itself  and  from  which  it  is  certain  to  spread  in  all  directions  if  not 
checked  or  exterminated  where  it  is,  it  will  be  clearly  seen  that  we 
have  to  deal  with  a  first-class  emergency  in  the  history  of  horti- 
culture in  this  State ;  one  which  calls  for  wisdom  in  counsel  and 
energy  in  action  as  few  other  things  have  done  since  horticulture 
first  began  to  assume  prominence  among  us  as  an  industrial 
pursuit. 

DESCRIPTION. 

The  female  of  the  San  Jose  scale — so  named  because  it  was 
first  detected  in  the  San  Jose  Valley  of  California — is  a  small, 
nearly  flat,  circular  scale,  from  a  twelfth  to  a  twenty-fifth  of  an 
inch  in  diameter,  of  a  general  gray  color  (light  or  dark)  with  a  pale 
yellow  or  reddish  yellow  center.  The  surface  of  the  full-grown 
scale  is  usually  smooth,  but  is  sometimes  slightly  marked  with 
concentric  rings.  The  scale  of  the  male  is  oblong  when  full  grown, 
usually  darker  than  that  of  the  female,  sometimes  approaching 
black.  It  is  marked  by  a  nipple-like  elevation  near  one  end,  sur- 
rounded by  a  little  groove-like  ring,  which  gives  it  a  very  charac- 
teristic appearance  under  a  good  hand  lens. 

The  surface  of  the  bark,  when  it  is  completely  covered,  has 
to  the  naked  eye  a  minutely  roughened,  incrusted,  and  unhealthy 
look,  and  a  dusky  or  dark  grayish  hue.  If  the  surface  be  rubbed 
by  the  finger,  it  will  have  a  greasy  feel,  due  to  an  oily  fluid  from 
the  crushed  insects.  Examined  under  a  good  glass,  the  nipple-like 
centers  of  the  young  scales  and  the  circular  grooves  surrounding 
these  give  a  very  characteristic  appearance  to  the  encrusted  sur- 
face. From  other  common  fruit  scales  it  is  very  readily  distin- 
guished, especially  in  the  winter,  by  its  circular  form,  by  its  smaller 
size,  and  by  the  absence  of  eggs  beneath  it.  The  other  common 
apple  scales  are  the  oyster-shell  bark-louse  and  the  scurfy  scale, 
both  of  which  are  oblong,  varying  in  length  from  a  tenth  to  a 
sixth  of  an  inch.  Under  each  scale  of  these  species  will  be  found 
at  this  season  a  little  collection  of  oval  eggs,  yellow  or  nearly 
white  under  the  oyster-shell  scale,  and  maroon-red  under  the 
scurfy  scale.  The  San  Jose  scale,  on  the  other  hand,  does  not 
commonly  lay  eggs,  but  brings  forth  its  young  alive. 


BULLETIN  NO.   48. 


[April, 


a. 

Fig.  i.*— San  Jos6  scale  on  bark:  a,  infested  twig,  natural  size;  b,   small    portion, 
magnified. 


Fig.  2.* — Adult  male,  greatly  enlarged. 

*From  Bull.  No.  3,  N.  S.,  U.  S.  Department  of  Agriculture,  Division  of  Entomology 
pp.  36  and  42. 


SAN   J°SE   SCALE   IN   ILLINOIS.  417 

LIFE   HISTORY. 

This  scale  passes  the  winter,  nearly  grown,  as  a  living  insect 
on  the  bark.  By  the  middle  of  May  the  young  begin  to  appear — 
minute  six-legged  oval  creatures,  visible  under  a  lens  as  crawling 
yellowish  specks.  After  creeping  about  for  a  few  hours,  the 
young  insect  thrusts  its  long  bristle-like  sucking  beak  through  the 
bark  of  the  plant  and  there  remains  motionless  during  the  remain- 
der of  its  life.  It  gradually  transforms  by  successive  molts  to  the 
circular  scale  already  described,  all  trace  of  legs  and  feelers  dis- 
appearing in  the  process.  This  account  of  its  transformations 
applies  to  the  female  only,  the  male  going  through  a  somewhat 
different  process,  and  emerging  as  a  minute  two-winged  fly. 
When  a  little  more  than  a  month  old  the  female  begins  to  bring 
forth  young,  at  least  four  successive  generations  occurring  in  our 
latitude  in  a  single  season.  The  progeny  of  a  single  female  may 
vary,  according  to  actual  count,  from  fifty  to  five  hundred  or  more, 
with  an  apparent  average  of  about  two  hundred  female  young  for 
each  female  of  the  generation  preceding.  According  to  these 
figures  the  production  of  a  single  female  insect  surviving  the 
winter  on  the  bark  would  amount  by  fall  to  over  a  billion  and  a 
half  of  female  scales.  "  It  is  not  to  be  expected,  of  course,"  says 
Mr.  Howard,  "that  all  the  individuals  from  a  scale  survive  and 
perform  their  function  in  life,  but  under  favorable  conditions,  or 
in  the  case  of  a  tree  newly  infested  or  not  heavily  incrusted,  the 
vast  majority  undoubtedly  go  through  their  existence  without 
accident.  Neither  the  rapidity  with  which  trees  become  infested 
nor  the  fatal  effect  which  so  early  follows  the  appearance  of  this 
scale  insect  is  therefore  to  be  wondered  at." 

FOOD    PLANTS. 

The  San  Jose  scale  attacks  nearly  every  variety  of  deciduous 
fruit  trees,  and  many  other  trees  and  various  shrubs  as  well.  It 
has  been  found  upon  the  peach,  apricot,  plum,  cherry,  pear,  quince, 
raspberry,  rose,  gooseberry,  currant,  persimmon,  elm,  osage 
orange,  pecan,  linden,  willow,  and  wahoo.  The  pear,  peach,  plum, 
apple,  and  cherry  are  almost  equally  liable  to  injury.  Certain 
varieties  of  pear  are,  however,  rarely  attacked,  notable  examples 
of  which  are  the  Leconte  and  Kieffer,  both  supposed  to  be  hybrids 
with  the  Chinese  sand  pear.  On  Mr.  Hayer's  premises  at  Sparta 
Kieffer  pears  remain  uninjured,  scattered  here  and  there  through 
an  orchard  where  almost  every  other  tree  is  thickly  incrusted. 
The  liability  of  this  scale  to  extend  to  osage  orange  hedges  is  a 
fact  which  must  be  especially  borne  in  mind,  since  it  often  makes 


418  BULLETIN  NO.  48.  [April, 

it  necessary  to  treat  the  fences  surrounding  an  orchard  as  a  part 
of  the  orchard  itself.  Whatever  tree  it  attacks  it  is  likely  to  infest 
throughout,  fastening  itself  indifferently  upon  trunk,  limbs,  leaves, 
and  fruit.  It  sometimes  kills  the  tree  outright,  although  badly 
infested  stock  may  maintain  a  feeble  existence  for  some  years. 
Young  peach-trees  will  ordinarily  survive  an  attack  of  this  scale 
two  or  three  years  at  most.  If  left  to  itself  it  spreads  quite  slowly, 
killing,  however,  as  it  goes,  everything  particularly  subject  to  its 
attack.  It  is  possible  that  the  young  scale  may  be  conveyed  to 
considerable  distances  by  flying  or  running  insects  or  by  birds; 
ordinarily,  however,  such  scattering  of  the  young  scale  will  have 
no  permanent  effect,  since  females  distributed  here  and  there,  one 
in  a  place,  would  be  little  likely  to  be  fertilized,  and  in  most  cases 
would  perish  without  reproduction.  I  have  lately  received,  how- 
ever, from  Professor  J.  M.  Stedman,  of  Missouri,  an  interesting  item 
of  information  touching  upon  the  agency  of  birds  in  the  distribu- 
tion of  this  scale.  In  the  vicinity  of  infested  orchards  in  Missouri 
Professor  Stedman  noticed  that  wherever  a  bird's  nest  was  seen 
the  San  Jose  scale  had  commonly  established  itself,  sometimes, 
indeed,  being  confined  to  the  branch  bearing  the  nest,  in  other 
cases  having  distributed  itself  more  generally  over  the  tree.  Evi- 
dently the  frequent  passage  of  birds  between  the  nest  and  the 
infested  orchard  had  resulted  in  the  frequent  transfer  of  the  young, 
probably  including  males  and  females  both,  and  in  the  establish- 
ment of  colonies  in  condition  to  perpetuate  themselves  and  to 
serve  as  further  centers  of  distribution. 

ORIGIN   AND   DISTRIBUTION. 

The  original  home  of  the  San  Jose  scale  has  not  yet  been  cer- 
tainly ascertained.  It  has  been  found  in  Australia,  Japan,  and 
Hawaii,  but  seems  to  have  been  first  recorded  from  Chili  in  1872, 
where  it  was  found  on  pears  which  had  been  introduced  from  the 
United  States.  By  1873  it  had  become  a  serious  pest  in  the  San 
Jose  Valley,  California,  on  the  premises  of  Mr.  James  Lick,  the 
founder  of  the  Lick  Observatory.  It  was  not  scientifically  de- 
scribed until  1880,  by  which  time  it  had  extended  as  far  west  as 
San  Francisco.  It  has  since  spread,  in  the  Pacific  region,  through- 
out California,  Oregon,  and  Washington,  and  has  reached  British 
Columbia  and  Idaho  on  the  north,  and  Nevada,  Arizona,  and  New 
Mexico  on  the  south.  Its  first  appearance  in  the  Atlantic  States, 
so  far  as  known,  was  on  plums  imported  to  New  Jersey  from  San 
Jose  in  the  spring  of  1886  or  1887.  It  was  not  actually  detected 
in  these  states,  however,  until  August,  1893,  at  which  time  it  was 
found  in  Charlottesville,  Virginia,  where  it  had  been  introduced 


SAN  JOSE   SCALE   IN   ILLINOIS.  419 

from  New  Jersey  nurseries.  Besides  the  states  above  mentioned, 
it  is  now  known  to  occur  in  Alabama,  Delaware,  Florida,  Georgia, 
Indiana,  Louisiana,  Massachusetts,  Maryland,  New  York,  Ohio, 
Pennsylvania,  West  Virginia,  Missouri,  and  Illinois. 

The  first  publication  of  its  occurrence  in  the  East  was  made 
by  Riley  and  Howard  in  February,  1894,  and  in  April  of  that  year 
twelve  thousand  copies  of  a  circular  of  warning  were  issued  by  Mr. 
Howard,  giving  general  notice  of  its  occurrence  in  several  Eastern 

States. 

PRECAUTIONARY   MEASURES   IN   ILLINOIS. 

Apprehensive  lest  it  should  already  have  made  its  way  to 
Illinois  through  importations  either  direct  from  California  or  from 
Eastern  States,  and  fully  appreciating  also  the  probability,  the 
practical  certainty,  indeed,  that  it  would  at  any  rate  ultimately 
appear  in  our  own  orchards,  the  general  subject  of  the  scale 
insects  of  the  State  was  assigned  in  July  of  this  same  year,  1894,  to 
Mr.  W.  G.  Johnson,  an  assistant  of  my  office  recently  engaged  from 
California,  where  he  had  become  well  acquainted  with  the  San 
Jose  scale.  During  the  two  following  years  numerous  collections 
of  the  orchard  scales  were  made  in  various  parts  of  the  State. 
A  paper  on  this  subject  was  prepared  for  the  Transactions  of  the 
State  Horticultural  Society,*  and  a  technical  article  containing 
descriptions  of  some  new  species  detected  in  the  course  of  Mr. 
Johnson's  studies  was  prepared  by  him  for  publication  in  the 
Bulletin  of  the  State  Laboratory  of  Natural  History.t 

During  all  this  work,  although  it  is  now  evident  that  the  San 
Jose  scale  was  present  in  the  State  at  the  time  in  several  localities, 
not  a  single  specimen  was  found  by  us — a  sufficient  proof,  if  any 
were  needed,  that  it  is  virtually  impossible  to  detect  such  first 
appearances  by  means  of  a  general  and  indiscriminate  search  con- 
ducted without  clues  to  probable  places  and  times  of  introduction. 
DISCOVERY  IN  ILLINOIS. 

The  first  hint  of  the  presence  of  the  San  Jose  scale  in  Illinois 
was  received  August  29,  1896,  from  Mr.  Chittenden,  an  Assistant 
in  Mr.  Howard's  entomological  office  in  Washington,  in  charge  of 
the  office  during  the  absence  of  his  Chief,  who  wrote  enclosing  a 
letter  from  Dr.  Groff,  of  Lewisburg,  Penn.,  reporting  that  he  had 
just  received  from  Mr.  Valentine  J.  Kiem,  of  Quincy,  111.,  the  San 
Jose  scale  "in  its  worst  form,"  and  asking  that  the  Entomologist 
of  this  State  be  notified.  I  later  learned  from  Mr.  Kiem  that  this 
report  was  based  on  specimens  sent  by  him,  with  a  request  for 
information,  to  Meehans'  "Gardeners'  Monthly." 

*  Vol.  28,  1894,  p.  170. 

t  Art.  XIII.,  Vol.  IV.,  p.  380. 


420  BULLETIN   NO.   48.  [April, 

I  immediately  wrote  to  Mr.  Kiem  for  specimens  cut  from  the 
injured  trees,  and  September  4th  received  from  him  pieces  of  twigs 
completely  incrusted  with  the  San  Jose  scale.  The  fact  of  the  oc- 
currence of  this  insect  in  Illinois  being  thus  established,  I  sent  my 
most  experienced  Entomological  Assistant,  Mr.  C.  A.  Hart,  to 
Ouincy  with  instructions  to  inspect  the  infested  premises  thor- 
oughly, and  to  extend  his  search  into  all  orchards,  nurseries,  and 
fruit  gardens  for  two  or  three  miles  around.  According  to  his  re- 
port, made  September  yth,  the  Quincy  attack  was  limited  to  about 
a  dozen  peach-  and  apple-trees  received  from  a  New  Jersey 
nurseryman  in  the  spring  of  1894,  and  set  in  an  isolated  orchard  of 
five  hundred  trees  some  three  miles  out  of  town. 

DISINFECTION   OF   QUINCY   ORCHARD. 

At  a  meeting  of  the  Executive  Board  of  the  State  Horti- 
cultural Society,  held  in  September,  1896,  the  facts  with  regard  to 
this  orchard  were  reported  to  this  Board,  who  thereupon  passed  a 
resolution  requesting  the  State  Entomologist  to  undertake  the 
extermination  of  the  scale  at  this  place,  and  making  an  appropria- 
tion (not  to  exceed  $150)  from  the  funds  of  the  Horticultural 
Society  for  the  expenses  of  this  procedure. 

On  a  personal  visit  to  Mr.  Kiem's  place,  made  a  few  days 
later,  I  came  to  an  agreement  with  him  that  he  should  permit 
nothing  to  leave  his  premises  which  could  possibly  convey  the 
scale  to  any  other  locality,  and  that  he  should  do  all  the  work  and 
provide  all  the  assistance  necessary  to  a  thorough  insecticide  treat- 
ment of  everything  on  his  farm  which  could  harbor  the  scale,  on 
condition  that  the  work  should  be  supervised  from  my  office  and 
that  the  insecticide  should  be  furnished  him  at  our  expense.  As 
the  female  scales  were  still  giving  birth  to  young  at  this  time,  I 
decided  to  postpone  operations  until  it  was  certain  that  all  the 
scales  in  the  orchard  were  established  in  fixed  position  on  the 
trees.  There  was  an  additional  advantage  in  waiting  until  the  leaves 
had  fallen,  as  a  smaller  quantity  of  insecticide  would  then  be 
required  for  a  thorough  treatment  of  the  trees,  shrubs,  and  hedges 
on  this  place. 

As  Mr.  J.  C.  Blair,  of  the  University  Department  of  Horti- 
culture, has  had  extensive  practical  experience  with  spraying 
methods  in  the  orchard,  I  gladly  availed  myself  of  his  kind  offer 
to  superintend  this  operation  for  us,  and  sent  him  November  10th 
on  a  general  trip  of  inspection  through  western  Illinois,  with  full 
instructions  as  to  the  disinfection  of  the  Quincy  orchard.  The 
insecticide  used  was  whale-oil  soap  obtained  from  Leggett  & 
Brother,  301  Pearl  Street,  New  York  City,  at  a  cost  of  four  cents 


SAN   J°SE   SCALE   IN    ILLINOIS  421 

per  pound  by  the  barrel.  This  soap  was  applied  in  a  hot  solution 
of  two  pounds  to  the  gallon  of  water.  In  the  operation  a  large 
iron  pot  holding  about  sixty  gallons  was  mounted  in  the  field  near 
the  orchard,  and  in  it  water  was  heated  and  the  soap  dissolved. 
This  soap  solution  was  taken  from  the  pot  boiling  hot  and  placed 
in  a  barrel  on  a  wagon  provided  with  an  ordinary  orchard  spray- 
pump  and  twenty-five  feet  of  hos"e  with  a  good  spray  nozzle. 
Three  men  were  required  for  the  work:  one  heating  the  water, 
one  driving  the  team  and  pumping,  and  the  third  handling  the 
hose.  'Nine  of  the  infested  trees  had  been  rooted  up  and  burned 
by  the  owner,  but  everything  else  in  the  orchard  was  thoroughly 
drenched.  Care  was  taken  that  every  twig  of  every  tree  was  thor- 
oughly soaked  with  this  hot  solution,  which  was,  however,  doubtless 
cold  by  the  time  it  struck  the  bark.  The  trees  were  carefully  exam- 
ined the  next  day  after  spraying,  and  all  parts  which  the  liquid 
had  not  certainly  reached  were  sprayed  again.  Patches  of  raspberry 
canes  adjoining  and  all  the  osage-orange  hedge  in  the  vicinity 
were  similarly  treated.  Five  hundred  and  ninety-five  pounds  of 
whale-oil  soap  were  thus  used,  or  a  total  of  two  hundred  and 
ninety-eight  gallons  of  fluid  for  the  five  hundred  trees.  The  one- 
and  two-year-old  stock  required  but  little  of  the  solution,  but  for 
trees  four  to  eight  years  old  an  average  of  two  and  a  half  quarts 
was  used.  For  some  of  the  larger  trees  in  the  older  part  of  the 
orchard  two  gallons  each  were  necessary.  Mr.  Blair  found  it 
expedient  to  direct  the  spray  himself,  not  wishing  to  trust  to  the 
thoroughness  of  persons  not  familiar  with  this  sort  of  work.  The 
cost  of  material  for  this  single  treatment  was  $23.80.  For  the 
larger  trees  it  was,  as  will  be  seen,  eight  cents  per  tree  for  the 
soap  alone. 

INSPECTION   OF   ILLINOIS   ORCHARDS. 

Learning  from  Mr.  Kiem  that  other  trees  had  to  his  knowl- 
edge been  received  from  New  Jersey  by  his  neighbors  at  about 
the  same  time  as  his  own,  I  decided  to  appeal  to  the  public  spirit 
of  these  outside  nurserymen  known  to  have  distributed  stock  at 
a  time  when  their  own  premises  were  infested  and  before  this  fact 
had  been  ascertained  by  them,  in  the  hope  of  securing  from  them 
lists  of  their  Illinois  customers  to  whom  this  suspected  stock  had 
been  sent  out.  By  correspondence  with  Professor  J.  B.  Smith,  the 
Experiment  Station  Entomologist  of  New  Jersey,  I  secured  the 
names  of  all  nurserymen  in  that  State  whose  premises  had  at  any 
time  been  infested  with  the  San  Jose  scale  and  who  had  an  out- 
side trade  in  nursery  stock.  To  my  great  pleasure,  these  gentle- 
men were  good  enough  to  send  me  lists  of  ourchasers  in  Illinois 


422  BULLETIN    NO.    48.  [April, 

to  whom  it  seemed  to  them  possible  that  infested  trees  or  shrubs 
had  at  any  time  been  sent.  The  total  number  of  Illinois  localities 
given  on  these  lists  was  one  hundred  and  nineteen,  and  the  num- 
ber of  persons  receiving  stock  from  these  suspected  localities  was 
one  hundred  and  forty-six  in  all.  These  localities  were  well  dis- 
tributed throughout  the  State,  from  Waukegan  and  Scales  Mound 
on  the  north  to  Villa  Ridge  on  the  south,  and  from  Paris  and  Dan- 
ville on  the  east  to  Moline,  Quincy,  and  Alton  on  the  west.  To 
all  persons  who  had  imported  this  suspected  stock  a  letter  of 
warning  and  advice  was  sent  from  my  office  October  22,  with  a  re- 
quest that  careful  inspection  of  this  material  should  be  made,  and 
that  specimens  should  be  sent  me  if  anything  of  a  suspicious 
character  was  found.  General  notice  of  the  facts  was  also  pub- 
lished through  the  agricultural  press  of  the  State  and  through  the 
Associated  Press. 

October  20th  I  began  to  visit,  either  personally  or  through  com- 
petent assistants,  the  places  on  our  list,  with  the  intention  of  look- 
ing up  and  inspecting  critically  every  lot  of  imported  stock  which 
we  had  reason  to  believe  might  possibly  harbor  the  scale.  Ninety- 
eight  localities  and  one  hundred  and  thirteen  orchards  and  nurs- 
eries have  been  visited  up  to  this  date,  with  the  result  to  discover,  as 
already  said,  fifteen  points  in  Illinois  now  known  to  us  to  be 
infested  by  the  San  Jose  scale.  At  each  of  two  of  these  we  found 
two  independently  imported  lots  of  trees  which  were  infested,  mak- 
ing seventeen  such  importations  thus  far  found  in  Illinois.  These 
infested  localities  are  as  follows,  beginning  at  the  north  part  of 
the  State:  Monroe  Center,  in  Ogle  county;  Tremont,  in  Tazewell 
county;  Quincy  and  Paloma,  in  Adams  ;  Auburn  and  New  City,  in 
Sangamon  ;  Tower  Hill,  in  Shelby  county  ;  Ernst,  in  Clark  county ; 
Collinsville,  in  Madison  county;  Mascoutah,  in  St.  Clair  county; 
West  Salem,  in  Edwards  county ;  Mt.  Carmel,  in  Wabash  county ; 
Richview,  in  Washington  county;  Sparta,  in  Randolph;  and  Villa 
Ridge,  in  Pulaski  county.  Availing  myself  of  the  Holiday  disper- 
sion of  our  entomological  students  to  their  homes,  and  putting  two 
inspectors  besides  into  the  field  for  regular  trips,  I  have  now  been 
able  to  provide  for  visits  to  nearly  all  the  other  points  requiring 
inspection. 

CONDITIONS   AT   INFESTED   LOCALITIES. 

The  exact  condition  of  affairs  with  respect  to  this  scale  re- 
ported by  my  inspectors  for  each  of  the  orchards  now  known  to 
be  infested  by  it  is  as  follows  : 

At  Monroe  Center,  in  Ogle  county,  one  pear-tree  in  a  small 
fruit  patch  was  found  badly  infested  with  the  scale,  the  other  trees 
in  the  lot  being,  so  far  as  could  be  seen,  entirely  free  from  it. 


SAN  JOSE   SCALE   IN   ILLINOIS.  423 

This  infested  tree  had  come  from  a  New  Jersey  nursery.  To  my 
letter  of  October  22d,  asking  him  to  inspect  his  imported  trees  and 
to  report  the  results,  the  owner  had  replied  that  he  had  carefully 
examined  all  his  New  Jersey  stock,  and  that  it  was  free  from 
scale.  I  mention  this  as  evidence  of  the  fact  that  the  fruit  grow- 
er's own  inspection  cannot  be  depended  on  with  safety  in  matters 
of  this  importance. 

Three  miles  south  of  Tremont,  in  Tazewell  county,  my  in- 
spector found  that  Mr.  Jacob  Winzeler  had  purchased  from  New 
Jersey  in  the  springs  of  1894  and  1895  a  considerable  number  and 
a  large  variety  of  trees,  mostly  pears  but  including  also  a  few 
apples,  plums,  and  cherries,  and  some  currant  bushes.  In  this 
orchard  six  Japanese  golden  russet  pears  were  quite  badly  in- 
fested by  the  scale.  As  these  were  set  alternately  with  trees  of 
other  varieties  which  showed  no  sign  of  the  scale  it  is  practically 
certain  that  they  were  infested  when  received,  and  it  is  probable 
that  the  scale  has  not  begun  to  spread.  The  owner  has  promised 
to  burn  these  trees,  but  we  have  no  present  assurance  that  the  re- 
mainder of  the  orchard  will  be  sprayed. 

The  Quincy  case  has  already  been  described.  The  other 
Adams  county  locality  at  which  the  scale  was  found  was  Paloma, 
a  small  town  on  the  Wabash  railroad.  Among  some  forty  or  fifty 
New  Jersey  trees  on  the  premises  of  Thomas  P.  Ogle  at  this  place 
only  one  was  found  infested  with  the  scale,  and  that  a  pear  which 
stood  by  itself  on  the  lawn.  This  was  dug  up  and  burned  by  Mr. 
Blair,  and  the  owner  of  the  orchard  has  promised  to  disinfect  the 
remainder  of  his  trees.  As  these  are  all  small,  it  can  be  done  at 
very  slight  expense. 

At  New  City,  in  Sangamon  county,  twelve  miles  south  of 
Springfield,  three  plum-trees  and  thirteen  pears  (Clapp's  favorite 
and  Garber)  belonging  to  Mr.  Henry  Archer  were  badly  infested 
with  the  scale.  These  trees  were  said  by  the  owner  to  be  grafts 
from  a  nursery  at  Louisiana,  Mo.,  but  as  he  had  received  many 
trees  from  New  Jersey  whose  location  he  was  not  sure  of,  it  seems 
probable,  on  the  whole,  that  this  was  the  source  of  the  scale.  The 
owner  promised  to  root  up  and  burn  the  trees  marked  for  destruc- 
tion by  Mr.  Blair,  but  did  not  feel  that  he  could  afford  to  disinfect 
his  entire  two-acre  orchard  with  whale-oil  soap. 

At  Auburn,  in  this  same  county,  nineteen  miles  south  of 
Springfield,  we  found  five  acres  of  fruit-trees  belonging  to  Mr.  I. 
N.  Lowe,  among  which  two  plum-trees,  eight  apple-,  eight  pear-, 
and  eleven  peach-trees,  all  imported  from  New  Jersey  about  five 
years  ago,  were  found  so  badly  infested  by  the  San  Jose  scale 
that  the  owner  was  advised  to  dig  them  up  and  burn  them.  The 


424  BULLETIN   NO.   48.  '.April, 

osage-orange  hedge  beside  this  orchard  plot  was  also  seriously 
attacked.  It  would  probably  require  six  hundred  pounds  of  whale- 
oil  soap  to  destroy  the  scale  on  these  premises,  together  with  a 
good  force-pump,  twenty  feet  of  hose,  and  other  appliances  not 
now  in  Mr.  Lowe's  possession.  To  raise  the  fifty  dollars  or  so 
which  a  thorough  disinfection  of  this  orchard  would  require,  the 
owner  assured  us  that  he  would  have  to  haul  corn  to  market  at 
thirteen  cents  a  bushel. 

Two  and  a  half  miles  east  of  Tower  Hill,  in  Shelby  county,  we 
found  two  hundred  New  Jersey  pear-trees  and  eight  hundred 
others,  together  with  apples,  blackberries,  etc.,  mostly  from  Illi- 
nois. Five  of  the  New  Jersey  trees  were  badly  infested  by  the 
scale,  and  three  others  slightly  so.  The  owner,  Mr.  G.  W.  Grisso, 
promised  to  burn  the  infested  trees. 

From  Ernst,  in  Clark  county,  twigs  from  a  dwarf  Duchess 
pear-tree  bought  in  the  spring  of  1804  from  a  Bridgeport,  Ohio, 
nursery,  were  sent  me  early  in  this  month  by  Mr.  William  C. 
Hammerly  with  the  request  that  I  would  identify  the  scale  upon 
them,  which  had  lately  attracted  his  attention.  These  twigs  were 
thoroughly  incrusted  with  the  San  Jose  scale,  although  a  dozen 
dwarf  pears  bought  at  the  same  time,  and  fifty  more  received  from 
the  same  source  in  the  spring  of  1895,  together  with  a  number  of 
peach-,  cherry-,  and  quince-trees,  were  reported  to  be  perfectly 
clean.  The  infested  tree,  however,  was  incrusted  from  the  surface 
of  the  ground  almost  to1  the  tips  of  the  twigs.  Advised  of  the 
presence  of  the  San  Jose  scale  by  my  reply,  Mr.  Hammerly  wrote 
me  on  the  roth  of  December  that  he  had  cut  the  tree  down, 
sprayed  it  thoroughly  with  kerosene  and  burned  it.  As  this  tree 
came  from  a  source  not  previously  known  to  be  infested  by  this 
scale,  some  correspondence  followed,  from  which  I  learned  that 
the  tree  came  to  this  State  through  a  jobber  or  dealer  in  trees  who 
had  no  nursery  of  his  own  but  who  had  bought  it  v/ith  a  quantity 
of  others  from  a  New  York  nurseryman  on  whose  grounds  the 
scale  has  never  been  known  to  occur.  On  a  subsequent  careful 
inspection  of  this  entire  neighborhood  no  other  infested  trees 
were  found. 

At  Collinsville,  in  Madison  county,  in  an  orchard  of  about  five 
acres  belonging  to  Charles  Eckert,  five  or  six  large  trees  (apricot 
and  plum)  were  found  slightly  infested  at  one  end  of  the  orchard, 
and  a  small  apple  near  the  center  of  it  was  extensively  attacked  by 
the  San  Jose  scale  and  other  orchard  scales.  The  latter  tree  had 
been  received  from  New  Jersey  three  years  ago,  and  had  been 
noticed  by  the  owner  as  unthrifty  from  the  beginning. 

At  Mascoutah,  in  St.  Clair  county,  about  ten  trees  were  found 
infested  with  the  San  Jose  scale  in  one  corner  of  a  neglected  fruit 


l8g-J,}  SAN  JOSE   SCALE   IN   ILLINOIS.  425 

plot  on  a  town  lot.  The  infested  trees  were  peach,  apple,  and 
cherry.  These  had  been  imported  originally  from  New  Jersey  by 
John  Baisch.  The  property  has  since  changed  hands. 

In  a  ten-acre  orchard  at  West  Salem,  Edwards  county,  belong- 
ing to  Mr.  Augustus  Fischel,  several  Nevada  pear-trees  originally 
obtained  from  a  New  Jersey  nursery  were  found  badly  infested 
with  the  San  Jose  scale,  one  of  the  trees  having,  in  fact,  died  from 
its  effects.  An  apricot  was  also  conspicuously  covered,  and  a  few 
peach-trees  near  by  were  slightly  contaminated. 

At  Mt.  Carmel,  in  Wabash  county,  a  single  infested  plum-tree 
has  been  found,  specimens  from  which  were  sent  me  by  Dr.  J. 
Schneck.  Particulars  have  not  yet  been  received. 

At  Richview,  in  Washington  county,  in  a  young  eight-acre 
orchard,  nearly  all  pears,  belonging  to  Dr.  J.  W.  Stanton,  a  large 
number  of  trees  were  found  dead  and  completely  covered  with  the 
San  Jose  scale,  the  greater  part  of  the  others  in  this  plot  being 
also  more  or  less  infested.  A  few  scales  were  found  even  on  the 
Kieffer  pears,  although  none  of  these  trees  were  seriously  affected. 
A  part  at  least  of  the  infested  trees  were  originally  from  New 
Jersey.  From  this  place  the  scale  has  spread  into  an  old  orchard 
adjoining,  belonging  to  Mr.  Rice.  A  few  San  Jose  scales  were 
also  found  in  a  small  pear  orchard  belonging  to  Jasper  Welgur  on 
stock  from  the  same  source  as  the  preceding. 

Much  the  most  serious  condition  of  affairs  with  respect  to  the 
San  Jose  scale  thus  far  found  by  us  is  that  disclosed  by  letters 
from  Mr.  J.  B.  Hayer,  at  Sparta,  Randolph  county,  and  by  the 
subsequent  report  of  an  inspector  from  my  office  who  visited  his 
place  last  December.  Mr.  Hayer's  New  Jersey  importations  were 
made  at  various  times  from  five  to  ten  years  ago,  and  since  that 
period  he  has  lost  about  a  thousand  bearing  apple-  peach-  and 
pear-trees  from  this  scale.  He  has  now  about  seven  hundred 
trees  on  his  farm,  all  of  which  except  his  Kieffer  pears  are  infested 
with  the  scale,  many  of  them  being  completely  incrusted.  The 
same  scale  was  found  on  this  farm  on  elm  trees,  wild  crab-apples, 
and  rose  bushes,  and  on  osage  orange  hedges  beside  the  orchard. 
It  has  also  spread  to  three  other  orchards  adjoining  on  the  north, 
west,  and  south.  Mr.  Hayer  has  applied  various  insecticides  from 
time  to  time,  some  of  them  with  moderate  success,  but  has  prac- 
tically given  up  trying  to  raise  peaches  and  apples  and  buys  now 
only  the  Kieffer  pear.  Another  fruit-grower  near  this  town,  Mr. 
John  Robinson,  has  also  imported  the  scale  from  the  same  New 
Jersey  situation,  and  has  it  now  on  peaches  and  on  the  Nevada 
pear. 


426  BULLETIN  NO.  48.  [April, 

From  Villa  Ridge,  in  Pulaski  county,  Mr.  C.  C.  Spaulding  sent 
me,  the  first  of  March,  pieces  of  twigs  from  a  Transcendent  crab- 
apple-tree  obtained  from  a  tree  dealer  in  Ohio  in  the  fall  of  1894, 
the  condition  of  which  had  attracted  his  attention  sufficiently  to 
lead  to  his  treating  it  with  pure  kerosene.  An  examination  of 
these  specimens  showed  that  they  were  thickly  covered  with  the 
San  Jose  scale.  Further  search  by  Mr.  Spaulding,  made  upon  the 
receipt  of  this  information,  resulted  in  the  sending  of  several 
additional  specimens  bearing  scale  insects,  none  of  which,  how- 
ever, were  of  this  species. 

It  will  be  seen  that  these  seventeen  Illinois  colonies  of  the  San 
Jose  scale  are  all  in  orchards  or  small  fruit  plots,  and  none  of  them 
in  nurseries.  In  every  case  thus  far  detected  the  original  importa- 
tion of  the  scale  was  made  directly  from  the  East  by  the  owner  of 
the  orchard,  and  not  through  any  Illinois  nursery.  On  the  other 
hand,  it  is  much  to  be  regretted  that  although  our  local  nursery- 
men have  frequently  dealt  with  proprietors  of  Eastern  nursery 
grounds  which  are  now  known  to  have  been  at  one  time  infested, 
my  inspectors  have  rarely  been  able  to  trace  any  stock  so  received 
beyond  the  Illinois  nursery  through  which  it  has  passed  to  Illinois 
customers ;  it  is  consequently  possible  that  some  cases  of  the 
occurrence  of  the  scale  will  thus  escape  our  search.  It  is  also 
worthy  of  remark  that  we  have  not  thus  far  found  any  cases  of 
infested  premises  where  the  scale  has  been  introduced  by  trade 
with  another  infested  point  within  the  State.  In  every  case  the 
immediate  start  has  come  from  outside  our  limits. 

PREVENTIVES   AND   REMEDIES. 

Methods  of  prevention  applicable  to  the  San  Jose  scale  are 
limited  to  precautions  against  its  introduction  on  to  premises 
previously  free.  With  the  numerous  possible  sources  of  contami- 
nation now  scattered  throughout  the  country,  no  fruit  grower  is 
really  safe  who  does  not  first  assure  himself  that  the  premises  from 
which  his  young  stock  may  be  obtained  are  themselves  free  from 
this  insect,  and  who  does  not  critically  inspect  every  portion  of 
every  tree  and  shrub  liable  to  attack  by  this  scale  which  comes  to 
his  premises.  The  best  evidence  of  the  absence  of  the  scale  from 
any  nursery  is  the  general  reputation  of  the  nurseryman  for  care, 
method,  and  honesty,  backed  by  a  certificate  of  inspection  from 
some  competent  entomological  expert,  presumably  a  state  or 
national  officer.  The  time  seems  rapidly  approaching  when  official 
inspection  and  certification  will  be  a  necessity  of  the  trade.  It  is 
to  be  remembered,  however,  that  an  inspection  of  the  premises  of 
a  nursery  and  a  certificate  of  freedom  from  the  scale  are  not  a 


SAN   JOSE   SCALE   IN   ILLINOIS.  427 

guarantee  of  all  stock  which  may  be  shipped  out  by  the  owner, 
since  a  large  percentage  of  that  sold  by  most  nurserymen 
originates  elsewhere.  The  rearing  of  nursery  stock  has  now 
become  largely  specialized  in  localities  to  the  great  advantage, 
indeed,  both  of  the  dealer  and  his  customer.  In  any  case  in  which 
the  purchaser  of  young  trees  suspects  the  possibility  of  the  pres- 
ence of  this  scale  he  should  at  least  thoroughly  disinfect  it  by 
dipping  or  washing  in  a  solution  of  whale-oil  soap,  to  be  presently 
described  as  the  standard  remedy  for  an  attack.  A  great  variety 
of  remedial  substances  have  been  more  or  less  generally  used  in 
different  parts  of  the  country,  and  have  likewise  been  extensively 
treated  experimentally  by  the  U.  S.  Department  of  Agriculture  in 
the  vicinity  of  Washington.  The  results  of  these  experiments 
indicate  that  conclusions  reached  and  practices  established  on  the 
Pacific  slope  cannot  be  depended  upon  in  a  widely  different 
climate.  At  present,  for  practical  purposes  it  seems  wise  to  limit 
the  recommendation  of  an  insecticide  to  a  solution  of  whale-oil 
soap,  two  pounds  to  a  gallon  of  hot  water,  made  and  used  as  stated 
in  this  paper  in  the  description  of  the  Quincy  experiment.  The 
reader  desirous  of  knowing  the  varieties  of  treatment  and  the 
results  of  experience  with  them  cannot  do  better  than  to  consult 
the  bulletin  on  the  San  Jose  scale  published  in  1896  by  the  U.  S. 
Department  of  Agriculture,  pages  56-71.  From  the  summary  of 
recommendations  in  this  bulletin  I  take  the  following: 

"  For  the  East,  experience  justifies  the  following  steps  as  of 
highest  importance : 

"(i)  In  all  cases  of  recent  or  slight  attack  the  affected  stock 
should  be  promptly  uprooted  and  burned.  No  measure  is  so  sure 
as  this,  and  the  danger  of  spread  is  so  great  that  this  course  seems 
fully  warranted. 

"(2)  In  case  of  long  standing  and  wide  extent  the  affected 
stock  should  be  cut  back  severely  and  treated  with  winter  soap 
wash.  Stock  badly  incrusted  with  scale  should  be  cut  out  at  once 
and  burned.  The  lessening  of  the  vitality,  together  with  the 
poisoning  of  the  sapwood  already  affected  by  the  scale  in  such 
cases,  will  usually  prevent  the  plant  from  ever  again  becoming 
healthy,  and  generally  it  is  beyond  help.  We  wish  particularly  to 
impress  upon  the  minds  of  fruit  growers  that  as  soon  as  this  insect 
is  found  to  occur  in  an  orchard  the  most  strenuous  measures  must 
be  taken  to  stamp  it  out.  No  half-way  steps  will  suffice.  The 
individual  must  remember  that  not  only  are  his  own  interests 
vitally  at  stake  but  those  of  the  entire  community  in  which  he 
resides.  He  may  think  that  he  cannot  bear  the  loss,  but  the  loss 
in  consequence  of  the  slightest  neglect  will  be  much  greater.  The 


428  BULLETIN  NO.  48.  \April, 

fact,  too,  that  there  is  a  community  of  interests  among  fruit 
growers  in  this  matter  must  not  be  lost  sight  of.  Fruit  growers 
must  be  mutually  helpful  in  an  emergency  like  this. 

"(3)  As  precautionary  measures  to  prevent  the  introduction 
of  the  scale  into  new  districts,  the  following  considerations  are 
important:  No  orchardist  should  admit  a  single  young  fruit  tree 
or  a  single  cutting  from  a  distance  into  his  orchard  without  first 
carefully  examining  it  and  satisfying  himself  conclusively  that  it 
does  not  carry  a  single  specimen  of  the  San  Jose  scale;  he  should 
insist,  also,  on  a  guaranty  from  the  nurseryman  of  such  freedom. 
In  addition,  no  fruit  should  be  brought  upon  the  premises  without 
previous  careful  inspection.  If  this  course  is  adopted  by  every 
one  interested,  without  exception,  the  rate  of  spread  of  the  species 
may  be  limited  to  the  comparatively  slight  natural  extension  by 
crawling,  by  winds,  and  by  the  aid  of  other  insects  and  birds." 

S.  A.  FORBES,  PH.  D:, 

Consulting  Entomologist, 


'8971 


INDEX. 


429 


INDEX. 


Agonoderus  pallipes 216 

Agriotes  mancus 226 

Allorhina  nitida 280 

Amaranthus  albus loo 

Amaranthus  spinosus 100 

Aphis  maidiradicis ....  236—7 

Apfiodius  granarius 217 

Apples,  University  orchard. 
Descriptions  of  varieties — 

Cole's  quince 307 

Coon's  red 308 

Gravenstein 303 

Hicks 308 

Higby  sweet 308 

Indiana  favorite . 308 

Jefferies 309 

Jonathan  of  Buler .    309 

Large  yellow  Siberian  crab.  ...    . .   309 

McLellan 309 

Mansfield  russet ...     310 

Ned 310 

Red  stripe. .  . ;      310 

Royal  limbertwig 310 

Sharp's  apple 311 

Sweet  bellflower 311 

Utter 311 

Westfield  seek-no-further 311 

William  prince 312 

History  of  orchard ....      297-300 

Identity  of  varieties 301 

Life  of  trees          304 

List    of  and    short    notes    on  varie- 
ties   307-47 

List  of  most  promising  varieties 305-6 

Pests  of 301 

Soil  treatment  for 301 

Testing  varieties 305 

Asaphfs  decolor atus 226,  228,   229 

Bacillus  rufans 286 

Barnyard  manure  with  corn   20,  177 

Bordeaux  mixture  for  potato  leaf  blight 

138,  140 

Broom-corn  smut — 

Experiments  with 389-99 

Historical  review  of 401-4 

Hosts  and  distribution    ....... 375-6 

Injuries  and  loss     376-80 

Life  history 380-8 

Prevention  of 405-6 

Relationships 373~5 

Burrill,  T.  J 348 

Carduus  arvensis 101. 


Chinch-bug — 

Barriers  and  traps,  extermination  ex- 
periments  70-6 

History  of  injury 25 

Injury  to  corn 9,  12,     14 

Muscardine  disease  of 25 

Chlaenius  tomentosus 272 

Cicada  tredecim,  disease  of 27 

Cintraclia  Sorghi 374,  404 

Cintraclia  Sorghi-vulgaris 404 

Clinton,  G.  P no,  140,  145,  372  d,  406 

Clivina  impressifrons 217 

Clover,  alternating  with  corn 20,  178 

Commercial  fertilizers  with  corn, ... 20,   177 

Cordyceps  melolontha 273 

Corn — 

Barren  stalks.... 6,  8,  10-12,  21,  167,  171 

Classification  of  varieties 6-7,   170 

Cobs,  per  cent,  in 167,  169,  355 

Cross-fertilization .2,  20-1 

Depth  of  cultivation 2,  19,  349-52 

Depth  of  planting 2,  18 

Early  varieties 7,8,  170 

Ears  per  acre 8,  q,  21,  167 

Ears  to  a  stalk 172 

Frequency  of  cultivation 2,     19 

Germination  of 8,  10-12 

Height 8,  10-12,  17,   167 

Injury  by  chinch-bugs  ..   9,12,     14 

Insects  injurious  to  seed  and  root. .    209-96 

Late  varieties. 7,8,  170 

Listing 24 

Loss  in  drying 8,  13-14,     18 

Maturity  of 165 

Medium  maturing  varieties 7,  8,   170 

Mixture  of  varieties 6 

Names  of  varieties 

6-7,  10-15,  21,  166,  168,  170,  354-5 

Planting  in  hills  or  drills 2,     19 

Rainfall  during  corn  seasons..  .3,  164,  350 

Rate  of  growth 17,  175,  178 

Removing  tassels 2 1-3 

Root  pruning 2,     19 

Rotation,      University      Experiments 

continued 2,  19-20,  176-8 

Source  of  seed 10-12,  166,  355 

Stalks  per  acre 167 

Temperature     during     corn     seasons 

3-  164,  350 

Testing  varieties. . .  i,  4-16,  163-73,  352~5 
Thickness  of  planting. .    .  .    .  .2,  19,  175-6 

Time  of  planting i,  16-18,  173-5 


430 


BULLETIN   NO.   48. 


\.Aprilr 


Treatment  of  variety  plats 165 

Variation  in  duplicate  plats 5 

Water,  per  cent,  as  husked.  .8,  13-14,     18 

Weight  100  ears ...    8,  9,   167 

Weight  per  bushel 8,  13-14,  167 

Yield  of  nubbins 8,9,     22 

Yield  of  varieties 

6-9,  13-15,  21,  166-70,  354 

Corn  ensilage,  digestibility  of 185-9 

Corn  fodder,  digestibility  of 195-200 

Corrosive  sublimate  for  potato  scab.  137,  140 
Cow  pea  ensilage,  digestibility  of  ....  189-92 

Crimson  clover 355~7 

Cyclocephala  immaculata 259,  263,  269 

Cycloloma  atriplicifolium 99 

Davenport,  E. .  .155,  160,  179,  357,  362,  371 

Diabrotica  longicornis 282,   287 

Diabrotica  i2-punctata 282,  284 

Digestion  experiments — 

Animals  employed 181 

Collection  of  dung 182-4 

Digestibility  of  corn  ensilage 185 

Digestibility  of  corn-fodder 195-200 

Digestibility  of  cow  pea  ensilage . .  189-192 
Digestibility  of  soja  bean  ensilage. . .  192-5 

Metabolic  products 200-1 

Methods  of  analysis 184-5 

Methods  of  feeding 182 

Methods  used 181 

Disease  of  chinch-bug.     See  Muscardine 

disease  of  chinch-bug 

Drainage  of  so-called  hard-pan  lands. 357-62 

Drasterius  elegans 224,  225 

Entomophthora  aphidis 47,     68 

Entomophthora  fresenii. 247 

Feeding  experiments  without  coarse  feed — 

Discussion 368-7 1 

Experiments 363—8 

Object 362 

Plan 363 

Feeding  standards 207 

Fertilizers — 

On  potatoes 133-6 

On  wheat  in  S.  Ill 153 

Food- 
Composition  of 202 

Digestibility  of 204-5 

Uses  of 206 

Forbes,  S.  A 76,  296,  427 

Fraser,  W.  J 155,  160,  179,  355 

Fungicides 140-145,  372^- 

Fungous    disease    of    chinch-bug.       See 

Muscardine  disease  of  chinch-bug. 
Fungous  diseases  of  potato — 

Bundle  blackening 139 

Dry  end-rot 139 

Interior  spotting 138-9 

Leaf  blight 137-8,  143-5 

Mildew 138 

Scab 136-7,  142-4 

Fusarium  Solani 139 

Gardner,  F.  D 24 

Hard-pan,  soil  experiments 357-62 

Hopkins,  C.  G 201,  208 


Hot  water  treatment —  PAGC. 

Broom-corn  smut 406 

Smuts  in  general 372*: 

Hypomyces  Solani 139 

Insecticides. 229-32,  250,279,  419-20,425-26 
Insects  injurious  to  seed  and  root  of  corn. 

Enemies  of 228.  247,  269-74,  286-7 

General  indications  of  injury 210-12 

Injurious  to  root 

Northern  corn  root  worm 287-96 

Plant  lice  and  mealy  bugs 235-57 

Southern  corn  root  worm 282-7 

White  grubs 257-81 

Injurious  to  seed. 

Ants 214-15 

Beetles  215-17 

Footless  maggots 218-20 

Six-legged  larvae 220-4 

Wireworms 2241-33 

Preventive  and  remedial  measures 

229-33,  247-53,  274-9,  287,  296 

Synopsis  of  injuries 212-13 

Ips  fasciatus 222 

Isaria,  forms  of 77 

Lac hnosterna  fusca 263,  264,  268 

Lachnosterna  gibbosa 263,  268,  271 

Lachtwsterna  hirticula 263,  264,  272 

Lachnosterna  ilicis 263 

Lachnosterna  implicita 268 

Lachnosterna  inversa 263,  265,  268 

Lachnosterna  rugosa  ...  .260,  261,  262,  263 

Lachnosterna  tristis 263 

Lactuca  Scariola 102 

Lasius  niger 243,  245,  253,  256 

Lasius  niger  alienus.  243,  245,  252,  253,  254 

Macrosporium  Solani 137 

McCluer,  G.  W 136,  348 

Mechanical  analysis  of  soils 359 

Melanotus  communis , 231 

Melanotus  fissilis 225 

Metarrhizius  anisoplia 228 

Meteorological  records — 

1889-1895 148,  164 

1889-1896 350 

Microphthalma  nigra 272 

Muscardine  disease  of  chinch-bug — 

on  Ataenius  stercorator ...      69 

on  Coccinella  q-notata 69 

Description  of  experiments  with 76 

Discussion  of  results  with 30-4 

on  Epicauta  vittata 69 

Experimental  methods  with 34~6 

on  Grapta  interrogationis 43 

on  Lachnosterna  larvae 273 

List  of  experiments  with 36-41 

on  Nabis  fusca 51 

on  Pieris  rapes 37,  43,  44,  46 

Myrmica  scabrinoJis  lobicornis 215 

Oats- 
Depth  of  sowing 1 57-8 

Methods  of  seeding 158 

Seed  per  acre 156-7 

Test  of  varieties 158-9 

Time  of  sowing 157 

Yields  per  acre 159 


INDEX. 


431 


Oospora  scabies 136 

Opkion  bifoveolatum 272 

Pelecinus  polyturator ...    27 1 

Pemphigus  pyri 297 

Penicillium  crustaceum 140 

Phorbia  fuscipes 218 

Physiological    requirements    of    animal 

body 362-7 1 

Potatoes — 

Cultivation 133 

Different  parts  for  seed 132 

Distance  apart 133 

Fertilizers 1 33—6 

Fungous  diseases  of 136—40 

Planting,  time  and  depth 132 

Second  crop 130 

Seed  from  best  and  poorest  hills. .  .129-30 

Seed  from  different  sources 127-9 

Size  of  seed  pieces 130-2 

Treatment  for  scab  and  leaf- blight.  .140-5 

Variety  tests 120-6 

Prionus  imbricornis. 281 

Prionus  laticollis 281 

Russian  thistle — 

Bibliography  of. 105-10 

Confusion  with  other  plants 99 

Control  of 99 

Description  of 90 

Distribution  of. 96 

Illustrations  of 111-14 

Influence  of 96-8 

Salsola    Kali    Tragus*      See    Russian 

thistle. 
San  Jose  scale  in  Illinois — 

Conditions  at  infested  localities  . . .  .421-5 

Description  of  scale 415 

Discovery  in  Illinois 418—19 

Disinfection  of  orchard 419-20 

Food  plants 416-17 

Importance  of  scale 413-15 

Inspection  of  orchards 420-1 

Life  history  of  scale 416 

Origin  and  distribution 417-18 

Precautionary  measures 418 

Preventives  and  remedies .425-27 


Schizoneura  panicola 236,  256 

Smuts  and  their  prevention 372  a-d 

Smuts  of  cereals  in  Illinois 372  b 

Smut  in  broom-corn 373-412 

Soja  bean  ensilage,  digestibility  of 192-5 

Solanum  Carolinense 100 

Solanum  rostratum 101 

Solenopsis  moles ta    214 

Sporotrichum  globuliferum.     See  Mus- 
cardine  disease  of  chinch-bug. 

Spraying  potatoes 138,  140—5 

Stysanus  stemonitis 140 

Systena  tceniata 221 

Tiphia  inornata 271,  272 

Tricothecium  roseum 140 

Ustilago  Keiliana 374 

Ustilago  cruenta 374,  375 

Ustilago  Sorghi 374,  375 

Ustilago  Zece 388 

Verticillium  cinnabarinum 140 

Weeds. 

Canada  thistle. 101 

Horse-nettle 100 

Pig-weed,  winged 99 

Prickly  lettuce 102 

Russian  thistle 87-1 18 

Sand-bur 101 

Thorny  amaranth 100 

Tumbleweed 100 

Weed  laws 102-5 

Whale  oil  soap  for  scale 419-20,  425-26 

Wheat. 

Fertilizers  S.  Illinois 153 

List  of  varieties 1 54-5 

Seed  per  acre 1 50-2 

Test  of  varieties I53~5 

Time  and  manner  of  harvesting. . .  147-50 

Time  of  sowing 1 52—3 

Weight  of  loo  kernels I54~5 

Weight  per  bu I54~5 

Yield  per  acre I54~S 

White  fungus.     See  Muscardine  dis- 
ease of  chinch-bug. 


432  BULLETIN   NO.   48.  [April, 

ORGANIZATION. 


BOARD  OF  TRUSTEES    UNIVERSITY  OF  ILLINOIS. 

FRANCIS  M.  McKAY,  Chicago,  President. 
JOHN  R.  TANNER,  Springfield,  Governor  of  Illinois. 
J.  IRVING  PEARCE,  Chicago,  President  State  Board  of  Agriculture. 
SAMUEL  M.  INGLIS,  Springfield,  Superintendent  Public  Instruction. 
JAMES  E.  ARMSTRONG,  Chicago.  ALEXANDER  McLEAN,  Macomb, 

NAPOLEON  B.  MORRISON,  Odin  MRS.  LUCY  L.  FLOWER,  Chicago 

ISAAC  S.  RAYMOND,  Sidney.  THOMAS  J.  SMITH,  Champnign. 

.SAMUEL  A.  BULLARD,  Springfield.        MRS.  MARY  TURNER  CARRIEL, 

Jacksonville. 
ANDREW  S.  DRAPER,  LL.D.,  President  of  the  University. 

ADVISORY  BOARD  OF  THE  EXPERIMENT  STATION. 

THOMAS  J.  BURRILL,  PH.D.,  Urbana,  Prof,  of  Botany  and  Horticulture,  Pres. 
A.  D.  BARBER,  Hamilton,  of  State  Board  of  Agriculture. 

E.  A.  RIEHL,  Alton,  of  State  Horticultural  Society. 
H.  B.  GURLER,  DeKalb,  of  State  Dairymen's  Association. 

N.  B.  MORRISON,  Odin,  Trustee  of  the  University. 

ISAAC  S.  RAYMOND,  Sidney,  Trustee  of  the  University. 

STEPHEN  A.  FORBES,  PH.D.,  Urbana,  Professor  of  Zoology. 

EUGENE  DAVENPORT,  M.  AGR.,  Urbana,  Professor  of  Animal  Husbandry. 

THE  STATION  STAFF. 

EUGENE  DAVENPORT,  M.  AGR.,  Agriculturist,  Director. 

WILLIAM  L.  PILLSBURY,  A.M.,  Urbana,  Secretary. 
THOMAS  J.  BURRILL,  PH.D.,  Horticulturist  and  Botanist. 

CYRIL  GEORGE  HOPKINS,   M.S.,  Chemist. 

.STEPHEN  A.  FORBES,  PH.D.,  Consulting  Entomologist. 

DONALD  McINTOSH,  V.S..  Consulting  Veterinarian. 

GEORGE  P.  CLINTON,  M.S.,  Assistant  Botanist. 

WILBER  J.  FRASER,  B.S.,  Assistant  in  Dairying. 

PERRY  G.  HOLDEN,  M.S.,  Assistant  Agriculturist. 

JOSEPH  C.  BLAIR,  Assistant  Horticulturist. 


^w 


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UNIVERSITY  OF  ILLINOIS-URBANA 


